Set A Product Minimum Across Products In Several Categories

Hi, Please forgive me if I started a new thread that has been previously addressed, but I've not been able to find a solution to what seems like a simple thing to do. I'm working for a client on a site that sells bread, they have two categories "Classic" and "Artistan". They would like to be able to force customers to purchase a minimum of three loaves based on any combination from both categories. I found where I could set a minum qty for an individual product, but is there any way to set a minimum qty at the category level that groups more than one category together? I am comfortable with PHP/MySQL, but new to zencart and not very familiar with the tables/structure yet, so any pointers or SQL/code examples on how to accomplish this would be very helpful.

You would have to write custom code to do this; there's nothing built in.

Hi, Swguy and all. I am selling apparels with severals catagories like tops, bottom, jackets etc and they are all under product general. I would like customer to have a minimum purchase of 5 pieces of products can be mix and match before they can checkout. Refer to Swguy says have to write custom code, how do I do about it. Or any other ways? Thanks, your help will be apprciated.